OpenStint

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Supported SDR Hardware ​

OpenStint works best with HackRF One and RTL-SDR v4. RTL-SDR v3 is also supported, but not recommended.

I recommend RTL-SDR v4 due to its price/performance ratio.

To learn more how SDR works, watch Andreas Spiess explaining it.

HackRF One vs RTL-SDR? ​

The HackRF One has lower noise, better thermal performance, similar dynamic range and a 3x-10x pricetag. Pick the RTL-SDR v4, unless you're a radio nerd with some money to spend.

If you build a track with a permament loop and decoder, consider the HackRF One due to it's better thermal management (more likely survives an installation in an enclosed electrical box).

HackRF One ​

HackRF One is an open-source radio. The orignal is manufactured by Great Scott Gadgets, and costs $330. Clones around $130 exists. I have successfuly tested one from Opensourcesdr Labs and Circet. Tips:

  • prefer the "clifford version", as it has extra input protection
  • do not purchase a portapack, as it is useless for laptiming application
  • bare PCBs (w/o housing) are cheaper options which might worth considering

RTL-SDR V4/V4L ​

Prefer the "original" RTL-SDR Blog v4. Thermal management is a known painpoint of these devices, and not every manufacturer is up to this challenge.

The V4 is no longer manufactured. The V4L (V4 Lite) is supported: OpenStint carries its own copy of the rtl-sdr driver, pinned to v2.0.3, which is the release that added V4L detection. You do not need a matching librtlsdr on your system, and having an older one installed does not interfere.

If you buy an off-brand, and it's overheating (it's not a neccessity, many manufacturer can indeed use the thermal paste and aluminium blocks), just attach a fan. Being hot is the normal operation, you have to just take some of that heat away.

RTL-SDR v3 ​

These devices do not have internal amplifiers for the required frequency range, you have to also buy external amplifiers/attenuators.

In direct sampling mode,

  • it's ca. 3 dB more sensitive than the v4. If you use V4 it with "-g 20" settings, you need a 3 dB attenuator to get the same results.
  • to use with an NE592-based "loop antenna amplifier", you need 20..30 dB attenuator with gain turned to minimum to get the same results.
  • the openstint-preamp is not usable, it detects the transponder from like 2 m away the loop; as it's bias-tee powered, you can not add attenuators